For a media device, such as a television set or a set top box, a user receives video programming that can be broadcasted through various means such as terrestrial, satellite, or cable. For example, in the United States, video programming is transmitted terrestrially via the use of radio frequency waves. The video programming is then accessed by a user via a television set or a set top box that demodulates, demultiplexes, and decodes a MPEG-2 transport stream that is transmitted on a specific frequency. Such a frequency is associated with a channel number called a physical channel. Hence, when a tuner tunes to a specified radio frequency, the tuner can use the mapping between a channel number for physical channel and the radio frequency that corresponds to such a physical channel. The relationships between physical channels and radio frequencies used for television broadcasts can be defined from a governmental agency such as the Federal Communication Commission (FCC) which is in charge of regulating the airwaves in the United States.
When an MPEG-2 stream is demultiplexed, a packet identifier table can be used to reconstitute various audio, video, and auxiliary data into video programming, where such programming is accessed by using channel numbers. In this setting, the channel information in a stream is called a virtual channel, where the channel number for the programming in an MPEG-2 stream does not have to be the same channel number associated with the radio frequency (physical channel number) used to transmit such programming. Additionally, video programming in an MPEG-2 stream can be accessed by using major and minor channels, where the major channel can be associated with a broadcaster, while a minor channel number can be associated with a sub-channel available from the broadcaster.
For example, the CBS station in Chicago is associated with channel 2, as a major channel, while the NBC station is associated with channel 5, as a different major channel. The programming from CBS can be further subdivided using minor channel numbers such that channel 2-1 is associated with a news broadcast, channel 2-2 is associated with weather information, and channel 2-3 is associated with the broadcast of game shows. These designations of virtual channel 2-1 and 2-2 do not have to correspond to the radio frequency for channel 2, but rather the real radio frequency used to broadcast the programming for “channel 2” can be on a different physical channel such as channel 10 or 12.
Regardless of whether the physical channel and the virtual channels are the same, the designations of major and minor channels (as virtual channels) are transmitted as part of the MPEG-2 information which is known as Program System Protocol Information (PSIP) as defined in accordance with Advanced Television System Committee N65 standard. Likewise, terrestrial virtual channel table information (TVCT) and cable virtual channel table information (CVCT) can also be transmitted as part of the PSIP information, where such tables define the relationship between virtual channels and the information transmitted as part of an MPEG-2 multiplex.
In contrast to the use of major and minor channels for television broadcast media services, the accessing of Internet based media services is not as easy as accessing television services. That is, with emergence of the Internet as a source of video and audio based media services, such Internet based media services are accessed using identifiers known as Uniform Resource Identifiers (URIs) or Internet Protocol (IP) addresses. Such identifiers however typically exist in the form of a large number of characters which are difficult to remember. Other forms of media services such as satellite radio, AM/FM radio, video on demand from service providers, Internet Protocol based television (IPTV) and the like, typically have their own unique identifiers, which do not use the major/minor channel combinations as used for satellite, terrestrial, or cable television.